This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In hydroxyl radical footprinting experiments, one of the major bottlenecks is in the data analysis. Due to the broad reactivity of hydroxyl radicals and the wide variety of oxidation products, it is very difficult to automate search algorithms for identification of sites of oxidation. Currently, manual validation and correction is necessary for all preliminary oxidation site assignments. A search algorithm named ByOnic was developed to allow for automated identification of a wide variety of post-translational modifications. This algorithm has been applied to hydroxyl radical footprinting with promising preliminary results. In collaboration with the developer of ByOnic, we will work to improve ByOnic for automated identification of sites of oxidation.